1. Field of the Invention
This invention relates to a touch panel, especially to an on-cell capacitive touch panel capable of effectively inhibiting reverse signals and enhancing signal uniformity.
2. Description of the Prior Art
In general, there are several different laminated structures of the capacitive touch panel. For example, in an on-cell capacitive touch panel, touch sensors are disposed on the outer surface of the glass of the display panel, so that display function and touch function can be integrally provided, and the laminated structure of the on-cell capacitive touch panel can become simpler. If the on-cell capacitive touch panel has no cover lens, the user can directly perform touch operation on the display panel.
Please refer to FIG. 1 and FIG. 2. FIG. 1 and FIG. 2 illustrate two different laminated structures of the on-cell capacitive touch panel respectively. The difference between the laminated structure 1 shown in FIG. 1 and the laminated structure 2 shown in FIG. 2 is that the laminated structure 1 shown in FIG. 1 includes cover lens 18 and optical clear adhesive (OCA)/optical clear resin (OCR) 16, but the laminated structure 2 shown in FIG. 2 does not.
It should be noticed that the laminated structure 2 shown in FIG. 2 having no cover lens 18 and OCA/OCR 16 can achieve the effects of simple laminated structure, reducing thickness, and saving costs; however, stronger reverse signals will be generated accordingly and multi-touch sensing performance of the on-cell capacitive touch panel will become poor.
For example, two touch points P1 and P2 in FIG. 3 are located at the upper left corner and the bottom right corner of the touch panel TP having the laminated structure 2 instead of being located at the same axis, the reverse signals are generated at a first location R1 and a second location R2 on the touch panel TP respectively, and the first location R1 and the second location R2 are located at the bottom left corner and the upper right corner of the touch panel TP; therefore, the reverse signals generated will not cancel out the touch signals of the two touch points P1 and P2. However, two touch points P3 and P4 in FIG. 4 are located at the same axis of the touch panel TP having the laminated structure 2, the reverse signals are generated at a third location R3 and a fourth location R4 on the touch panel TP respectively, and the third location R3 and the fourth location R4 will overlap the two touch points P3 and P4; therefore, the reverse signals generated will cancel out the touch signals of the two touch points P3 and P4, and the multi-touch sensing performance of the touch panel TP will become poor.
Therefore, the invention provides a capacitive touch panel to solve the above-mentioned problems.